I found it thanks. I don't seem to have much vacuum going to the front. Guess I will start looking for leaks or blockage. Thanks for the help everybody.
vacuum issues... HELP
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Joined: Dec 2012
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From: newaygo michigan
vacuum issues... HELP
Ive got an 81 with vacuum problems. Over the winter I did a few simple projects and now all of a sudden, my headlights came up, but they wont go back down. I changed the heater core, I did a simple tune up, plugs, wires, pcv, gas filter and replaced the AIR pump that was froze up. I am totally stumped. Any ideas?
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
The default position for the headlamps is "UP" so just guessing I'd say you knocked one of the small hoses off... or you have pulled down the over-ride switch.
Check the over-ride first then use the chart below.. I would go to point A on the small hoses by the relay's.. pull this loose and see if you have vacuum there and if you do, then check the two nipples on the relays and see if they have vacuum. If not them move back toward the dash and check for vacuum on 8.. if not vacuum there check on C at the small nipple of the check valve.
On your car it's a pretty simple system... for the headlamps to come down you must have vacuum on the small hose. They are what pulls the plunger to the down position. When you lose this vacuum (hose off or defective item) your headlamps default to the up position.
Check the over-ride first then use the chart below.. I would go to point A on the small hoses by the relay's.. pull this loose and see if you have vacuum there and if you do, then check the two nipples on the relays and see if they have vacuum. If not them move back toward the dash and check for vacuum on 8.. if not vacuum there check on C at the small nipple of the check valve.
On your car it's a pretty simple system... for the headlamps to come down you must have vacuum on the small hose. They are what pulls the plunger to the down position. When you lose this vacuum (hose off or defective item) your headlamps default to the up position.
Last edited by Willcox Corvette; Mar 5, 2013 at 08:17 PM.
Melting Slicks
Joined: Jul 2005
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From: Aurora Ontario
Jim
Last edited by jdp6000; Mar 6, 2013 at 08:46 AM.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Remove the PVC and plug the hose....any better?
Remove the hose to the air pump and block it....any better?
Did you have the air cleaner off? does yours have a hose to it? did you reconnect it?
Do each separate.
Jim
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Joined: Dec 2012
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From: newaygo michigan
Thanks Jim. I think the filter before the check valve is almost plugged. Gonna order one tomorrow from C.C. because I need some other stuff too. I checked this morning and the heater control wasn't working right and they both feed off of that line. Hope that's the problem. Think Ill order the check valve too. Ill let you know what happens.
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